Area codes 781 and 339

Area code 781 covers most of the Boston suburbs roughly along Route 128 and about two-thirds of the South Shore. It was created as a split from area code 617 on September 1, 1997. (LATA code 128). Use of 781 became mandatory February 1, 1998. 339 has been sharing the service area since May 2, 2001. Since then, 10 digit local dialing is mandatory.

Some mobile phone numbers from the 1990s assigned to rate centers in 781 and 339 kept the 617 area code just on those mobile lines after it was split.

Portions of the following counties are covered:

(781)-NXX

(339)-NXX

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